Plating apparatus and plating liquid removing method

ABSTRACT

A plating apparatus and a plating liquid removing method removes a plating liquid remaining on a substrate-contacting portion, or portions in its vicinity, of a substrate holding member. The plating apparatus comprises a head having a rotatable housing provided with a substrate holding member for holding a substrate, a plating process container, disposed below the head, for holding a plating liquid therein, and a plating liquid removing mechanism for removing plating liquid remaining on the substrate-contacting portion, or the portions in its vicinity, at an inner circumferential edge of the substrate holding member.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a plating apparatus and a platingliquid removing method, and more particularly to a plating apparatususeful for filling a metal such as copper into recesses forinterconnects formed in a semiconductor substrate, and a method forremoving plating liquid remaining on a substrate-contacting portion, orportions in its vicinity, of a substrate holding member for use in theplating apparatus.

2. Description of the Related Art

Generally, aluminum or aluminum alloy has been used as a material forforming interconnect circuits on a surface of a semiconductor substrate.Higher integrated density on the semiconductor substrate requires that amaterial having a higher electric conductivity should be used forinterconnect circuits. Therefore, there has been proposed a methodcomprising plating a surface of a substrate to fill interconnectpatterns, formed in the substrate, with copper or a copper alloy.

Various methods such as chemical vapor deposition (CVD) process,sputtering process, and the like have been used to fill interconnectpatterns, formed in a substrate, with copper or a copper alloy. However,when a metallic layer on a substrate is formed of copper or a copperalloy, i.e., when copper interconnects are formed on the substrate, theCVD process requires high cost, and, if an aspect ratio is high (i.e., adepth of the pattern is larger than a width thereof), then it isdifficult to fill the interconnect patterns with copper or a copperalloy during a sputtering process. Therefore, the aforementioned platingmethod is most effective to fill interconnect patterns, formed in asubstrate, with copper or a copper alloy.

There are various methods for plating a surface of a semiconductorsubstrate with copper. For example, in a cup-type plating method, adip-type plating method, or the like, a plating tank always holds aplating liquid, and a substrate is dipped into the plating liquid. Inanother plating method, a plating tank holds a plating liquid only whena substrate is fed into a plating container. Further, in an electrolyticplating method, an electric potential difference is applied to plate asubstrate. On the other hand, in an electroless plating method, anelectric potential difference is not applied.

In cup-type plating apparatuses, a substrate is held by a substrateholding member with a peripheral edge and a back surface of thesubstrate being sealed, and plating is performed by contacting anexposed front surface of the substrate with a plating liquid. After thisplating treatment, plating liquid is likely to remain on asubstrate-contacting portion, or portions in its vicinity, of asubstrate holding member. This remaining plating liquid, when dried, canproduce undesired particles. Moreover, the remaining plating liquid canadhere to a subsequent substrate to be plated, leading to aninsufficient plating of this substrate.

A method has been developed for removing such a plating liquid remainingon the substrate-contacting portion, or portions in its vicinity, of asubstrate holding member. According to this method, a plating liquidremoving device, having an absorbent for absorbing a plating liquid, ora sucking tool for sucking a plating liquid, is allowed to move in acircumferential direction along the substrate-contacting portion, orportions in its vicinity, of a substrate holding member so as to removeby absorption or suction plating liquid remaining on thesubstrate-contacting portion or portions in its vicinity.

The above conventional plating apparatuses that carry out this method,however, have the following drawbacks. The conventional apparatuses areso designed that the substrate holding member is fixed stationarilywhile the plating liquid removing device is allowed to rotate. Thismakes it impossible to conduct dewatering (spin-drying) of thesubstrate-contacting portion, or portions in its vicinity, of thesubstrate holding member. Since a large quantity of plating liquid thusremains, it is necessary to conduct a plating liquid removing operationfor every plating treatment. Moreover, each plating liquid removingoperation requires a considerably long time. Furthermore, removal of thelarge a quantity of plating liquid leads to consumption of an increasedamount of plating liquid, resulting in an increased production cost.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above drawbacks inthe related art. It is therefore an object of the present invention toprovide a plating apparatus and a plating liquid removing method whichcan easily and quickly remove plating liquid remaining on asubstrate-contacting portion, or portions in its vicinity, of asubstrate holding member, and which allows for a simplified apparatusstructure that requires a smaller space for installation.

According to a first aspect of the present invention, there is provideda plating apparatus, comprising: a head having a rotatable housingprovided with a substrate holding member for holding a substrate; aplating process container, disposed below the head, for holding aplating liquid therein; and a plating liquid removing mechanism forremoving plating liquid remaining on a substrate-contacting portion, orportions in its vicinity, at an inner circumferential edge of thesubstrate holding member.

The above apparatus can effectively remove the liquid remaining on thesubstrate-contacting portion, or portions in its vicinity, at the innercircumferential edge of the substrate holding member, forcibly. This canavoid a problem of particle generation that would be caused by unremovedplating liquid after it has dried. A possible dissolution of a seedlayer of a subsequent substrate by unremoved plating liquid can also beavoided. Further, the above apparatus, which allows the substrateholding member to rotate, makes it possible to remove plating liquidand, in addition, eliminates a need to rotate the plating liquidremoving mechanism.

In a preferred aspect of this invention, the plating liquid removingmechanism has a plating liquid suction nozzle which can move close tothe substrate-contacting portion at the inner circumferential edge ofthe substrate holding member and suck plating liquid remaining on thesubstrate-contacting portion, or the portions in its vicinity.

The plating liquid suction nozzle may have an arc shape extending alongthe substrate-contacting portion of the substrate holding member, andmay be designed to be movable in vertical and horizontal directions. Useof such a suction nozzle can carry out the of plating liquid remainingon the substrate-contacting portion, or the portions in its vicinity,efficiently in a short time.

In a preferred aspect of this invention, the plating liquid removingmechanism also has a cleaning liquid injection nozzle which can moveclose to the substrate-contacting portion at the inner circumferentialedge of the substrate holding member and eject a cleaning liquid towardthe substrate-contacting portion, or portions in its vicinity.

With this construction, the cleaning liquid injection nozzle ejects acleaning liquid, e.g. pure water, toward the substrate-contactingportion, or the portions in its vicinity, at the inner circumferentialedge of the substrate holding member, thereby cleaning thesubstrate-contacting portion, or the portions in its vicinity. Further,plating liquid remaining on the substrate-contacting portion, or theportions in its vicinity, is suction-removed, together with cleaningliquid, by the plating liquid suction nozzle. This can prevent platingliquid from remaining inside the plating liquid suction nozzle andclogging the nozzle after the liquid has dried.

According to a second aspect of this invention, there is provided aplating apparatus, comprising: a head having a rotatable housingprovided with a substrate holding member for holding a substrate; and aplating process container, disposed below the head, for holding aplating liquid therein; wherein the substrate holding member is providedwith a sealing member for sealing an outer peripheral edge of thesubstrate, with the sealing member being made of a highlywater-repellent material.

With this construction, the sealing member, which is to be contactedwith the substrate, is made of a highly water-repellent material. Thiscan reduce an amount of plating liquid that remains on a surface of thesealing member. Silicone rubbers may be used as the highlywater-repellent material. Ordinary silicone rubbers, however, have apoor durability. In order to ensure a sufficiently high tensilestrength, it is preferred to use a high-tearing strength silicone rubberhaving enhanced tensile strength. Use of such a specific rubber providesa sealing member having both a good sealing property and highdurability.

According to a third aspect of this invention, there is provided aplating apparatus, comprising: a head having a rotatable housingprovided with a substrate holding member for holding a substrate; aplating process container, disposed below the head, for holding aplating liquid therein; and a plating liquid removing mechanism forremoving a plating liquid remaining on a substrate-contacting portion,or portions in its vicinity, at an inner circumferential edge of thesubstrate holding member; wherein the substrate holding member isprovided with a sealing member for sealing an outer peripheral edge ofthe substrate, with the sealing member being made of a highlywater-repellent material.

According to a fourth aspect of this invention, there is provided aplating apparatus, comprising: a head having a rotatable housingprovided with a substrate holding member for holding a substrate; and aplating process container, disposed below the head, for holding aplating liquid therein; wherein the substrate holding member is providedwith a sealing member for sealing an outer peripheral edge of thesubstrate, with the sealing member having a substrate-contacting portionwhich is in a shape of a spire, in cross section, with a flat topsurface.

With this construction, the specific configuration of the sealing memberat the substrate-contacting portion can enhance rigidity of thesubstrate-contacting portion, and furthermore, and can cause platingliquid to remain on an inner side of the top flat surface, thereby notallowing the plating liquid to flow to an outer side (electrical contactside). This is advantageous because plating liquid, if flowed to theouter side, would not sufficiently be suction-removed and would stillremain.

According to a fifth aspect of this invention, there is provided aplating apparatus, comprising: a head having a rotatable housingprovided with a substrate holding member for holding a substrate; aplating process container, disposed below the head, for holding aplating liquid therein; and a plating liquid removing mechanism forremoving a plating liquid remaining on a substrate-contacting portion,or portions in its vicinity, at an inner circumferential edge of thesubstrate holding member; wherein the substrate holding member isprovided with a sealing member for sealing an outer peripheral edge ofthe substrate, with the sealing member having a substrate-contactingportion which is in a shape of a spire, in cross section, with a flattop surface.

According to a sixth aspect of this invention, there is provided amethod for removing a plating liquid remaining on a substrate-contactingportion, or portions in its vicinity, at an inner circumferential edgeof a substrate holding member for holding a substrate, comprising:rotating the substrate holding member to remove plating liquid from thesubstrate holding member; and sucking plating liquid remaining on thesubstrate-contacting portion, or portions in its vicinity, of thesubstrate holding member, while the substrate holding member is rotated.

According to a seventh aspect of this invention, there is provided aplating method, comprising: plating a substrate held by a substrateholding member of a rotatable housing; rotating the housing to remove aplating liquid remaining on the substrate and the substrate holdingmember; removing the substrate from the housing; and sucking platingliquid remaining on a substrate-contacting portion, or portions in itsvicinity, at an inner circumferential edge of the substrate holdingmember, while the substrate holding member is rotated.

According to an eighth aspect of this invention, there is provided aplating apparatus comprising: a head having a rotatable housing providedwith a substrate holding member for holding a substrate; a platingprocess container, disposed below the head, for holding a plating liquidtherein; and a plating liquid removing mechanism for removing a platingliquid remaining on a substrate-contacting portion, or portions in itsvicinity, at an inner circumferential edge of the substrate holdingmember; wherein the plating liquid removing mechanism has a platingliquid sucking member which is allowed to be introduced into the housingthrough an opening of the housing and to move near to the substrateholding member, with the plating liquid sucking member, when located soas to face the substrate holding member, sucking and removing platingliquid remaining on the substrate-contacting portion, or the portions inits vicinity, at inner circumferential edge of the substrate holdingmember, while the substrate holding member is rotated.

According to a ninth aspect of this invention, there is provided aplating method, comprising: plating a substrate held by a substrateholding member of a rotatable housing; rotating the housing to remove aplating liquid remaining on the substrate and the substrate holdingmember; removing the substrate from the housing through an opening ofthe; causing a plating liquid-sucking member of a plating liquidremoving mechanism to face the substrate holding member by introducingthe plating liquid removing mechanism into the housing through theopening; and removing plating liquid remaining on thesubstrate-contacting portion, or portions in its vicinity, at an innercircumferential edge of the substrate holding member in such a statethat the plating liquid-sucking member closely faces the substrateholding member, while the substrate holding member is rotated.

The above and other objects, features, and advantages of the presentinvention will be apparent from the following description when taken inconjunction with the accompanying drawings which illustrates preferredembodiments of the present invention by way of example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A through 1C are cross-sectional views showing an example of aplating process utilizing a plating apparatus according to the presentinvention;

FIG. 2 is a plan view showing a layout of a plating apparatus accordingto a first embodiment of the present invention;

FIG. 3 is an explanatory view showing an air current in the platingapparatus shown in FIG. 2;

FIG. 4 is a cross-sectional view showing an entire structure of aplating unit at a time of performing a plating process in the platingapparatus shown in FIG. 2;

FIG. 5 is a schematic diagram showing flow of a plating liquid in theplating apparatus shown in FIG. 2;

FIG. 6 is a cross-sectional view showing an entire structure of theplating unit at a time of not performing a plating process (at a time oftransfer of a substrate);

FIG. 7 is a cross-sectional view showing an entire structure of theplating unit at a time of maintenance;

FIG. 8 is a cross-sectional explanatory view of a relationship among ahousing, a pressing ring, and a substrate at a time of transfer of thesubstrate;

FIG. 9 is an enlarged view showing a part of FIG. 8;

FIGS. 10A through 10D are schematic explanatory views of flow of aplating liquid at a time of performing a plating process and at a timeof not performing a plating process;

FIG. 11 is an enlarged cross-sectional view showing a centeringmechanism in the plating unit;

FIG. 12 is a cross-sectional view showing a feeding contact (probe) inthe plating unit;

FIG. 13 is a plan view showing a plating liquid removing mechanism inthe plating unit;

FIG. 14 is a front view showing the plating liquid removing mechanismshown in FIG. 13;

FIG. 15 is a perspective view of a main portion of the plating liquidremoving mechanism.

FIGS. 16A through 16C are enlarged cross-sectional views of a mainportion of a sealing member;

FIGS. 17A and 17B are diagrams illustrating problems encountered uponusing a conventional sealing member; and

FIG. 18 is a graph showing change in contact angle for fluorinerubber-and silicone rubber-sealing members before and after 762.65-hourdipping in plating liquid.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A plating apparatus according to embodiments of the present inventionwill be described below with reference to the accompanying drawings.

A plating apparatus according to embodiments of the present invention isused for plating a surface of a semiconductor substrate with copper, forthereby manufacturing semiconductor devices on which interconnectshaving a copper layer are formed. This plating process will be describedbelow with reference to FIGS. 1A through 1C.

As shown in FIG. 1A, an insulating film 2 of SiO₂ is deposited over aconductive layer 1 a on a semiconductor base 1 having semiconductordevices, and then a contact hole 3 and a trench 4 for an interconnectare formed by lithography and etching technology. A barrier layer 5 madeof TiN or the like is formed on the insulating film 2, and a copper seedlayer 7 as an electric supply layer for an electrolytic plating isformed on the barrier layer 5 by sputtering or the like.

Subsequently, as shown in FIG. 1B, a surface of a substrate W is platedwith copper. Hence, the contact hole 3 and the trench 4 on thesemiconductor base 1 are filled with copper, and a copper layer 6 isformed on the insulating film 2. Thereafter, the copper layer 6 on theinsulating film 2 is removed by chemical mechanical polishing (CMP) sothat a surface of the copper layer 6 filled in the contact hole 3 andthe trench 4 is made substantially even with a surface of the insulatingfilm 2. Thus, as shown in FIG. 1C, an interconnect comprising copper 6is formed.

A plating apparatus for electrolytically plating a semiconductorsubstrate W according to a fist embodiment of the present invention willbe described below with reference to FIG. 2. As shown in FIG. 2, theplating apparatus is disposed in a rectangular facility 10, and isconstituted so as to plate a semiconductor substrate with coppercontinuously. The facility 10 has a partition wall 11 for dividing thefacility 10 into a plating section 12 and a clean section 13. Air canindividually be supplied into and exhausted from each of the platingsection 12 and the clean section 13. The partition wall 11 has a shutter(not shown) capable of opening and closing. Pressure of the cleansection 13 is lower than atmospheric pressure and higher than pressureof the plating section 12. This can prevent air in the clean section 13from flowing out of the facility 10 and can prevent air in the platingsection 12 from flowing into the clean section 13.

In the clean section 13, there are provided two cassette stages 15 forplacing a substrate cassette thereon, and two cleaning and drying units16 for cleaning (rinsing) a plated substrate with pure water and dryingthe substrate. Further, a rotatable fixed-type first transfer device(tetraxial robot) 17 for transferring a substrate is provided in theclean section 13. For example, each cleaning and drying unit 16 hascleaning liquid supply nozzles for supplying ultrapure water to bothsurfaces of a substrate, and spins the substrate at a high speed todewater and dry the substrate.

On the other hand, in the plating section 12, there are provided twopre-treatment units 21 for pre-treating a surface of a substrate forplating, and inverting the pre-treated substrate by a inverter 20, fourplating units 22 for plating a surface of a substrate with copper insuch a state that a front surface of the substrate faces downwardly, andtwo first substrate stages 23 a, 23 b for holding a substrate placedthereon. Further, a rotatable mobile-type second transfer device(tetraxial robot) 24 for transferring a substrate is provided in theplating section 12.

In the clean section 13, there are provided two chemical liquid cleaningunits 25 for cleaning a plated substrate with chemical liquid, andsecond substrate stages 26 a, 26 b disposed between the chemical liquidcleaning units 25 and the cleaning and drying units 16. A rotatablefixed-type third transfer device (tetraxial robot) 27 for transferring asubstrate is provided between the two chemical liquid cleaning units 25.

One of the first substrate stage 23 b and the second substrate stage 26b are constituted so as to clean a substrate with water. Each of thefirst substrate stage 23 b and the second substrate stage 26 b has aninverter 20 for inverting a substrate.

Thus, the first transfer device 17 transfers a substrate between thesubstrate cassettes placed on the cassette stages 15, the cleaning anddrying units 16, and the second substrate stages 26 a, 26 b. The secondtransfer device 24 transfers a substrate between the first substratestages 23 a, 23 b, the pre-treatment units 21, and the plating units 22.The third transfer device 27 transfers a substrate between the firstsubstrate stages 23 a, 23 b, the chemical liquid cleaning units 25, andthe second substrate stages 26 a, 26 b.

The transfer device 17 has two recess-type hands, respectively forsupporting a peripheral edge of a substrate by a recess. An upper handis used for handling a dry substrate and a lower hand is used forhandling a wet substrate. Each of the transfer devices 24 and 27 has tworecess-type hands, which are used for handling a wet substrate. Thehands of the transfer devices are not limited to those types describedabove.

In the present embodiment, the plating apparatus comprises the chemicalliquid cleaning units 25 for cleaning a surface of a substrate withchemical liquid such as dilute hydrofluoric acid or hydrogen peroxide.If it is not necessary to clean a plated substrate with chemical liquid,the chemical liquid cleaning units 25 are not required. In this case,the first transfer device 17 transfers a substrate between the substratecassettes placed on the cassette stages 15, the cleaning and dryingunits 16, and the first substrate stages 23 a, 23 b to thus dispensewith the third transfer device 27 and the second substrate stages 26 a,26 b.

Next, a processing flow of a substrate in the plating apparatusaccording to the present embodiment will be described below. Substratesare accommodated in a substrate cassette in such a state that frontsurfaces of the substrates (surfaces on which semiconductor devices areformed, i.e., surfaces to be processed) face upwardly, and the substratecassette accommodating such substrates is placed on a cassette stage 15.The first transfer device 17 removes a substrate from the substratecassette, moves to the second substrate stage 26 a, and places thesubstrate on the second substrate stage 26 a. Then, the third transferdevice 27 transfers the substrate from the second substrate stage 26 ato the first substrate stage 23 a. Thereafter, the second transferdevice 24 receives the substrate from the first substrate stage 23 a andtransfers the substrate to pre-treatment unit 21. After pre-treatment ofthe substrate is completed in the pre-treatment unit 21, the substrateis inverted by inverter 20 so that the front surface of the substratefaces downwardly, and is then transferred to the second transfer device24. The second transfer device 24 transfers the substrate to a head ofplating unit 22.

After the substrate is plated and liquid on the substrate is removed inthe plating unit 22, the substrate is received by the second transferdevice 24, which transfers the substrate to the first substrate stage 23b. The substrate is inverted by inverter 20 provided at the firstsubstrate stage 23 b so that the front surface faces upwardly, and isthen transferred to chemical liquid cleaning unit 25 by the thirdtransfer device 27. In the chemical liquid cleaning unit 25, thesubstrate is cleaned with chemical liquid and rinsed with pure water,and then liquid on the substrate is removed by spinning the substrate.Thereafter, the substrate is transferred to the second substrate stage26 b by the third transfer device 27. Next, the first transfer device 17receives the substrate from the second substrate stage 26 b, andtransfers the substrate to cleaning and drying unit 16. In the cleaningand drying unit 16, the substrate is rinsed with pure water and thenspin-dried. The dried substrate is returned to the substrate cassetteplaced on the cassette stage 15 by the first transfer device 17.

FIG. 3 is a schematic view showing an air current in the facility 10. Inthe clean section 13, a fresh external air is introduced through a pipe30 and pushed into the clean section 13 through a high-performancefilter 31 by a fan. Hence, down-flow clean air is supplied from aceiling 32 a to positions around the cleaning and drying units 16 andthe chemical liquid cleaning units 25. A large part of the suppliedclean air is returned from a floor 32 b through a circulation pipe 33 tothe ceiling 32 a, and pushed again into the clean section 13 through thehigh-performance filter 31 by the fan, to thus circulate in the cleansection 13. A part of the air is discharged from the cleaning and dryingunits 16 and the chemical cleaning liquid units 25 through a pipe 34 toan exterior of the clean section 13, so that pressure of the cleansection 13 is set to be lower than atmospheric pressure.

The plating section 12 having the pre-treatment units 21 and the platingunits 22 therein is not a clean section (but a contamination zone).However, it is not acceptable to attach particles to a surface of asubstrate. Therefore, in the plating section 12, fresh external air isintroduced through a pipe 35, and down-flow clean air is pushed into theplating section 12 from ceiling 37 a through a high-performance filter36 by a fan, for thereby preventing particles from being attached to thesurface of the substrate. However, if the entire flow rate of thedown-flow clean air is supplied by only an external air supply andexhaust, then enormous air supply and exhaust are required. Therefore,air is discharged through a pipe 38 to an exterior of the platingsection 12, and a large part of down-flow clean air is supplied bycirculating air through a circulation pipe 39 extended from a floor 37b, in such a state that pressure of the plating section 12 is maintainedto be lower than pressure of the clean section 13.

Thus, air returned to ceiling 37 a through the circulation pipe 39 ispushed again into the plating section 12 through the high-performancefilter 36 by the fan. Hence, clean air is supplied into the platingsection 12 to thus circulate in the plating section 12. In this case,air containing chemical mist or gas emitted from the pre-treatment units21, the plating units 22, the second transfer device 24, and a platingliquid regulating tank 40 is discharged through the pipe 38 to theexterior of the plating section 12. Thus, pressure of the platingsection 12 is controlled so as to be lower than pressure of the cleansection 13.

FIG. 4 shows a main part of the plating unit 22. Plating unit 22 mainlycomprises a plating process container 46 of a substantially cylindricalform for holding a plating liquid therein, and a head 47 disposed abovethe plating process container 46 for holding a substrate. In FIG. 4, thehead 47 is located in a plating position in which a substrate W held bythe head 47 is lowered.

The plating process container 46 is provided with a plating container 50including a plating chamber 49, which is upwardly opened, for holding aplating liquid therein. An anode 48 made of residual-phosphorus copper,for example, is provided at a bottom of the plating chamber 49. Theanode 48 is made of copper containing 0.03% to 0.05% phosphorus(residual-phosphorus copper), and hence a black film is formed on anupper surface of the anode 48 as plating proceeds. Such a black film canreduce generation of anode slime.

Plating solution supply nozzles 53 horizontally projecting toward acenter of the plating chamber 49 are provided on an innercircumferential wall of the plating container 50 at equal intervalsalong a circumferential direction. Each of the plating liquid supplynozzles 53 is communicated with a plating liquid supply passage extendedvertically through an interior of the plating container 50.

Further, according to this embodiment, a punch plate 220 having a largenumber of holes with a size of, for example, about 3 mm is disposed at aposition above the anode 48 within the plating chamber 49. The punchplate 220 prevents a black film formed on the upper surface of the anode48 from curling up by the plating liquid 45 and consequently beingflowed out.

The plating container 50 has first plating liquid discharge ports 57 forwithdrawing plating liquid 45 contained in the plating chamber 49 from aperipheral portion of the bottom of the plating chamber 49, and secondplating liquid discharge ports 59 for discharging plating liquid 45which has overflowed a weir member 58 provided at an upper end of theplating container 50. Further, the plating container 50 has thirdplating liquid discharge ports 120 for discharging plating liquid beforeoverflowing the weir member 58. Plating liquid which has flowed throughthe second plating liquid discharge ports 59 and the third platingliquid discharge ports 120 join at a lower end of the plating container50, and then is discharged from the plating container. Instead ofproviding the third plating liquid discharge ports 120, as shown inFIGS. 10A through 10D, the weir member 58 may have, in its lower part,openings 222 having a predetermined width at predetermined intervals sothat the plating liquid 45 passes through the openings 222 and is thendischarged to the second plating liquid discharge ports 59.

With this arrangement, when an amount of plating liquid supplied islarge during plating, the plating liquid is discharged to an exterior ofthe plating unit 22 through the third plating liquid discharge ports120, or is passed through the openings 222 and discharged to theexterior of the plating unit through the second plating liquid dischargeports 59 and, in addition, as shown in FIG. 10A, the plating liquidoverflows the weir member 58 is discharged to the exterior of theplating unit through the second plating liquid discharge ports 59. Onthe other hand, during plating, when an amount of plating liquidsupplied is small, the plating liquid is discharged to an exterior ofthe plating unit through the third plating liquid discharge ports 120,or alternatively as shown in FIG. 10B, the plating liquid is passedthrough the openings 222 and discharged to the exterior of the platingunit through the second plating liquid discharge ports 59. In thismanner, this construction can easily cope with a case where an amount ofplating liquid supplied is large or small.

Further, as shown in FIG. 10D, through holes 224 for controlling aliquid level, which are located above the plating liquid supply nozzles53, and communicate with the plating chamber 49 and the second platingliquid discharge ports 59, are provided at circumferentiallypredetermined pitches. Thus, when plating is not performed, the platingliquid is passed through the through holes 224, and is discharged to theexterior of the plating unit through the second plating liquid dischargeports 59, thereby controlling a liquid level of the plating liquid.During plating, the through holes 224 serve as an orifice forrestricting an amount of plating liquid flowing therethrough.

As shown in FIG. 5, the first plating liquid discharge ports 57 areconnected to reservoir 226 through plating liquid discharge pipe 60 a,and a flow controller 61 a is provided in the plating liquid dischargepipe 60 a. The second plating liquid discharge ports 59 and the thirdplating liquid discharge ports 120 join with each other within theplating container 50, and a joined passage is then connected directly tothe reservoir 226 through the plating liquid discharge pipe 60 b.

The reservoir 226 is constructed so that plating liquid from all theplating units flows into the reservoir 226. Plating liquid which hasflowed into the reservoir 226 is introduced by a pump 228 into theplating liquid regulating tank 40 (see FIG. 3). This plating liquidregulating tank 40 is provided with a temperature controller 230, and aplating liquid analyzing unit 232 for sampling plating liquid andanalyzing a sample solution. When a single pump 234 is operated, platingliquid is supplied from the plating liquid regulating tank 40 throughfilter 236 to the plating liquid supply nozzles 53 in each of theplating units. A control valve 56 is provided in plating liquid supplypipe 55 extending from the plating liquid regulating tank 40 to each ofthe plating units. This control valve 56 serves to make pressure on asecondary side constant, and, even when one plating unit is stopped, thecontrol valve 56 can make supply pressure of plating liquid in the otherplating units constant.

Thus, a plating liquid prepared in a plating liquid regulating tank 40in a single plating process system is fed to a plurality of platingunits through a single pump 234. The plating liquid preparation tank 40having a large capacity is used in a plating process system to prepare aplating liquid. With this arrangement, plating liquid is fed to each ofthe plating units while controlling flow rate in each of the platingunits through control valves 56, and a variation of the plating liquidwith regard to quality can be suppressed.

As shown in FIG. 4 a vertical stream regulating ring 62 and a horizontalstream regulating ring 63 are disposed within the plating chamber 49 ata position near an internal circumference of the plating chamber 49, anda central portion of a liquid surface is pushed up by an upward streamout of two divided upward and downward streams of plating liquid 45within the plating chamber 49, whereby downward flow is smoothened anddistribution of current density is further uniformized. The horizontalstream regulating ring 63 has a peripheral portion which is fixed to theplating container 50, and the vertical stream regulating ring 62 isconnected to the horizontal stream regulating ring 63.

On the other hand, the head 47 comprises a housing 70 which is arotatable and cylindrical receptacle having a downwardly open end andopenings 96 on a circumferential wall thereof, and vertically movablepressing rods 242 having, at their lower ends, respectively, pressingrings 240. As shown in FIGS. 8 and 9, an inwardly projecting ring-shapedsubstrate holding member 72 is provided at a lower end of the housing70. A ring-shaped sealing member 244 is mounted on the substrate holdingmember 72. The ring-shaped sealing member 244 projects inwardly, and afront end of a top surface of the ring-shaped sealing member 244projects upwardly in an annular tapered form. Further, contacts 76 for acathode electrode are disposed above the sealing member 244. Air ventholes 75, which extend outwardly in a horizontal direction and furtherextend outwardly in an upwardly inclined state, are provided in thesubstrate holding member 72 at circumferentially equal intervals.

With this arrangement, as shown in FIG. 6, a liquid level of platingliquid is lowered, and as shown in FIGS. 8 and 9, substrate W is held bya robot hand H or the like, and is inserted into the housing 70 wherethe substrate W is placed on an upper surface of the sealing member 244of the substrate holding member 72. Thereafter, the robot hand H iswithdrawn from the housing 70, and pressing ring 240 is then lowered tosandwich a peripheral portion of the substrate W between the sealingmember 244 and a lower surface of the pressing ring 240, thereby holdingthe substrate W. In addition, upon holding of the substrate W, a lowersurface of the substrate W is brought into pressure contact with thesealing member 244 to seal this contact portion positively. At the sametime, current flows between the substrate W and the contacts 76 for acathode electrode.

Returning to FIG. 4, the housing 70 is connected to an output shaft 248of a motor 246, and rotated by energization of the motor 246. Thepressing rods 242 are vertically provided at predetermined positionsalong a circumferential direction of a ring-shaped support frame 258rotatably mounted through a bearing 256 on a lower end of a slider 254.The slider 254 is vertically movable by actuation of a cylinder 252,with a guide, fixed to a support 250 surrounding the motor 246. Withthis construction, the pressing rods 242 are vertically movable byactuation of the cylinder 252, and, in addition, upon holding of thesubstrate W, the pressing rods 242 are rotated integrally with thehousing 70.

The support 250 is mounted on a slide base 262 which is engaged with aball screw 261 and vertically movable by the ball screw 261 rotated byenergization of the motor 260. The support 250 is surrounded by an upperhousing 264, and is vertically movable together with the upper housing264 by energization of the motor 260. Further, a lower housing 266 forsurrounding the housing 70 during plating is mounted on an upper surfaceof the plating container 50.

With this construction, as shown in FIG. 7, maintenance can be performedin such a state that the support 250 and the upper housing 264 areraised. A crystal of plating liquid is likely to deposit on an innercircumferential surface of the weir member 58. However, when the support250 and the upper housing 264 are raised, a large amount of platingliquid is flowed and overflows the weir member 58, and hence the crystalof the plating liquid is prevented from being deposited on the innercircumferential surface of the weir member 58. A cover 50 b forpreventing splashing of plating liquid is integrally provided in theplating container 50 to cover a portion above plating liquid whichoverflows during a plating process. By coating an ultra-water-repellentmaterial such as HIREC (manufactured by NTT Advance Technology) on alower surface of the cover 50 b for preventing splashing of platingliquid, a crystal of the plating liquid can be prevented from beingdeposited on the lower surface of the cover 50 b.

Substrate centering mechanisms 270 located above the substrate holdingmember 72 of the housing 70 for performing centering of substrate W, areprovided at four places along a circumferential direction of the housingin this embodiment (see FIG. 13).

FIG. 11 shows substrate centering mechanism 270 in detail. Eachsubstrate centering mechanism 270 comprises a gate-like bracket 272fixed to the housing 70, and a positioning block 274 disposed within thebracket 272. This positioning block 274 is swingably mounted through asupport shaft 276 horizontally fixed to the bracket 272 at its upperpart. Further, a compression coil spring 278 is interposed between thehousing 70 and the positioning block 274. Thus, the positioning block274 is urged by the compression coil spring 278 so that the positioningblock 274 rotates about the support shaft 276, and a lower portion ofthe positioning block 274 projects inwardly. Upper surface 274 a of thepositioning block 274 serves as a stopper, and is brought into contactwith lower surface 272 a of the bracket 272 to restrict movement of thepositioning block 274. Further, the positioning block 274 has a taperedinner surface 274 b which is widened outwardly in an upward direction.

With this construction, a substrate is held by the hand H of a transferrobot or the like, is carried into the housing 70, and is placed on thesubstrate holding member 72 (see FIG. 8). In this case, when a center ofthe substrate deviates from a center of the substrate holding member 72,the positioning block 274 is rotated outwardly against an urging forceof the compression coil spring 278 and, upon the release of holding ofthe substrate from the hand of the transfer robot or the like, thepositioning block 274 is returned to an original position by the urgingforce of the compression coil spring 278. Thus, centering of thesubstrate can be performed.

FIG. 12 shows a feeding contact (a probe) 77 for feeding power to acathode electrode plate 208 of a contact 76 for a cathode electrode.This feeding contact 77 is composed of a plunger and is surrounded by acylindrical protective member 280 extending to the cathode electrodeplate 208, whereby the feeding contact 77 is protected against platingliquid.

In this case, when a plating process is performed, an annularsubstrate-contacting portion 360 (see FIGS. 16A-16C) projecting from aninner circumferential surface of the sealing member 244, is pressedagainst a surface, to be plated, of the substrate. An inner side of thesubstrate-contacting portion 360 is filled with plating liquid.Therefore, plating liquid remains on the substrate-contacting portion orportions in its vicinity. This plating liquid, upon drying, becomes asource for particles. For this reason, in this embodiment, a platingliquid removing mechanism 300 is provided for removing plating liquidremaining on the substrate-contacting portion, or the portions in itsvicinity, of the sealing member 244.

FIGS. 13 through 15 show the plating liquid removing mechanism 300. Theplating liquid removing mechanism 300 includes a nozzle head 302 of anarc shape with a central angle of e.g. about 100° extending along thesubstrate-contacting portion 360 at an inner circumferential edge of thesealing member 244. Inside the nozzle head 302, a plating liquid passage302 a and a cleaning liquid passage 302 b are formed substantially inparallel, extending in a long direction of the nozzle head 302. At eachend of the nozzle head 302, there is provided a bottom-opened suctionnozzle 302 c that communicates with the plating liquid passage 302 a,and two bottom-opened cleaning liquid injection nozzles 302 d thatcommunicate with the cleaning liquid passage 302 b. The cleaning liquidinjection nozzles 302 d are disposed on both sides of the plating liquidsuction nozzles 302 c at each end of the nozzle head 302.

The nozzle head 302 is connected, through a block 306, to a lower end ofa nozzle support 304 that extends horizontally and turns halfway down toa vertical direction and extends downwardly. Inside the nozzle support304, there are formed a plating liquid passage 304 a and a cleaningliquid passage 304 b, which respectively communicate with the platingliquid passage 302 a and the cleaning liquid passage 302 b. The platingliquid passage 304 a is connected, via a flexible tube 312 a, to avacuum source 310; and the cleaning liquid passage 304 b is connected,via a flexible tube 312 b, to a cleaning liquid supply source 313.

The nozzle support 304 is connected to a horizontal slider 316 thatmoves horizontally by the actuation of a cylinder 314 for horizontalmovement. The cylinder 314 for horizontal movement is connected, througha hooked bracket 322, to a vertical slider 320 that moves vertically byactuation of a cylinder 318 for vertical movement. The cylinder 318 forvertical movement is mounted on the above described support 250.Therefore, the nozzle head 302 is horizontally and vertically movable.

FIGS. 16A-16C are an enlarged views of a main portion of the sealingmember 244. Substrate-contacting portion 360, which has a shape of aspire in cross section and projects upwardly, is formed at the innercircumferential upper edge of the sealing member 244. An outline of thesubstrate-contacting portion 360 is defined by: a top flat surface 362which is positioned slightly outwardly from a plane extending upwardlyfrom an inner circumferential end surface of the sealing member 244 andextends horizontally; a reverse tapered surface 364 which makes an acuteangle θ₁ with a horizontal plane and extends inwardly from the top flatsurface 362; and a tapered surface 366 which makes an acute angle θ₂with a horizontal plane and extends outwardly from the top flat surface362. Thus, the substrate-contacting portion 360 has a shape of anacute-angle triangle in cross section, with its top being flattened. Theangle θ₁ between the reverse tapered surface 364 and the horizontalplane is designed to be larger than the angle θ₂ between the taperedsurface 366 and the horizontal plane(θ₁>θ₂).

Due to this specific configuration, the substrate-contacting portion 360of the sealing member 244 possesses an enhanced rigidity. Further,provision of the reverse tapered surface 364 on an inner platingliquid-contacting side can keep plating liquid on the inner reversetapered surface 364, after a plating treatment, thus not allowing theplating liquid to flow to an outer side. Thus, as shown in FIG. 16B,when plating is performed while contacting substrate W with thesubstrate-contacting portion 360 and pressing the substrate W byapplying a sufficient load F to fully seal an outer peripheral edge ofthe substrate W, the plating liquid P stays between the substrate W andthe reverse tapered surface 364. After the substrate W is removed, theplating liquid P is stemmed by the top flat surface 362 and preventedfrom flowing down to an outer electrical contact side.

In a case of a conventional sealing member commonly used, as shown inFIGS. 17A and 17B, the sealing member has a substrate-contacting portion(sealing portion) 384 which has a shape of an obtuse-angle triangle, incross section, with two tapered surfaces 380 and 382 making an obtuseangle with each other. A substrate is sealed at a pointed top of thesubstrate-contacting portion 384. When plating is performed whilecontacting substrate W with the substrate-contacting portion 384 andpressing the substrate W by applying a sufficient load F to fully sealan outer peripheral edge of the substrate W, as shown in FIG. 17B, a topof the substrate-contacting portion 384 is forced to hang down beneaththe substrate W due to the load F, and plating liquid P remains betweenthe substrate W and the thus hung portion of the sealing member. Whenthe substrate W is removed and the substrate-contacting portion 384, dueto its elasticity, is restored to an original state, the plating liquidP flows down to an outer electrical contact side, as shown in FIG. 17A.

Plating liquid, which has flown down to the outer electrical contactside, is hard to remove by suction and becomes a source of generatingparticles. Moreover, the plating liquid corrodes electrical contactsand, in addition, forms a local electric cell between the electricalcontacts and the substrate-contacting portion 384, whereby an appearanceof the substrate is deteriorated. According to this embodiment of thepresent invention, plating liquid is prevented from flowing to the outerelectrical contact side, and therefore, the above drawbacks can beavoided.

Further, according to this embodiment, the sealing member 244 is made ofa high-tearing strength silicone rubber that has a higherwater-repellency than that of a fluorine rubber and anethylene/propylene rubber, and has a sufficiently high tensile strength.Use of such a highly water-repellent sealing member 244, which is to becontacted with a substrate, can reduce an amount of plating liquid thatremains on a surface of the substrate.

Specifically, conventional sealing members are generally made of afluorine rubber or an ethylene/propylene rubber. FIG. 18 showscomparative data regarding a change of contact angle (θ) between asealing member made of a fluorine rubber and a sealing member made of asilicone rubber having a higher water-repellency, in which contact angledata for respective members after 762.65-hour dipping in a platingliquid is shown together with data for undipped members. As shown inFIG. 18, in the case of the sealing member made of fluorine rubber, thecontact angle decreases from 80° (undipped member) to 76° (dippedmember), indicating deterioration of water-repellency. In contrast,there is seen no substantial change in contact angle (from 91° to 92°)for the sealing member made of silicone rubber, thus indicating nodeterioration of water-repellency.

Ordinary silicone rubbers have a tensile strength of about 8 MPa (80kgf/cm²), which is half the tensile strength of fluorine rubbers, i.e.about 16 MPa (160 kgf/cm²). In the case of a high tearing-strengthsilicone rubber, on the other hand, this rubber has an enhanced tensilestrength of about 10-12 MPa (100-120 kgf/cm²). A sealing member made ofthis particular silicone rubber thus does not suffer from a shortage ofstrength.

Operation of plating unit 22 will now be described.

First, in transferring a substrate to plating unit 22, an attractinghand of the second transfer device 24 shown in FIG. 2, and substrate Wattracted and held with its front surface facing downwardly by theattracting hand, are inserted into the housing 70 through opening 96,and the attracting hand is then moved downwardly. Thereafter, vacuumattraction is released to place the substrate W on the substrate holdingmember 72. The attracting hand is then moved upwardly and withdrawn fromthe housing 70. Thereafter, the pressing ring 240 is lowered down to aperipheral edge of the substrate W so as to hold the substrate W betweenthe substrate holding member 72 and the lower surface of the pressingring 240.

Plating liquid 45 is then spurted from the plating liquid supply nozzles53 while, at the same time, the housing 70 and the substrate W heldthereby are allowed to rotate at a middle speed (100-250 rev/min, e.g.150 rev/min). When the plating chamber is charged with a predeterminedamount of plating liquid 45, and further after an elapse of severalseconds, a rotational speed of the housing 70 is decreased to a slowrotation (10-225 rev/min, e.g. 100 rev/min). Then, electroplating iscarried out by flowing a plating current between the anode 48 and asurface, to be plated, of the substrate as a cathode.

After feed of the plating current, as shown in FIG. 10D, an amount ofsupply of plating liquid is decreased so that the plating liquid isallowed to flow out only through the through holes 224, for liquid levelcontrol, positioned above the plating liquid supply nozzles 53, therebyexposing the housing 70, together with the substrate held thereby, abovea surface of the plating liquid. The housing 70 and the substrate W,positioned above the liquid surface, are allowed to rotate at a highspeed (e.g. 500-1000 rev/min) to remove the plating liquid by action ofcentrifugal force. After completion of dewatering, rotation of thehousing 70 is stopped so that the housing stops at a predeterminedposition.

After the housing 70 comes to a complete stop, the pressing ring 240 ismoved upwardly. Thereafter, the attracting hand of the second transferdevice 24 is inserted, with its attracting face directed downwardly,into the housing 70 through the opening 96 and is then lowered to aposition at which the attracting hand can attract the substrate. Afterattracting the substrate by vacuum attraction, the attracting hand ismoved upwardly to a position of the opening 96 of the housing 70, and iswithdrawn, together with the substrate held by the hand, through theopening 96.

According to the plating unit 22, the head 47 can be designed to becompact and structurally simple. Further, plating can be performed whena surface of plating liquid in the plating process container 46 lies ata plating level, and dewatering and transfer of the substrate can beconducted when a surface of the plating liquid lies at a substratetransferring level. Moreover, black film formed on a surface of anode 48can be prevented from being dried and oxidized.

When the above-described plating treatment is repeatedly performed, anamount of plating liquid remaining on the substrate-contacting portion360, or portions in its vicinity, of the sealing member 244 graduallyincreases though the sealing member 244 used is made of a high-tearingstrength silicone having a high water-repellency, and the plating liquidremaining on the substrate-contacting portion 360, or the portions inits vicinity, of the sealing member 244 is removed by centrifugal forceby rotating the substrate at a high speed. Accordingly, for everyseveral times (for example five times) of plating treatments, or at anytime according to need, suction-removing of plating liquid remaining onthe substrate-contacting portion 360, or the portions in its vicinity,of the sealing member 244 is conducted by using the plating liquidremoving mechanism 300. A suction-removing treatment may of course beconducted for every plating treatment.

Specifically, dewatering (spin-drying) is performed by rotating thehousing 70 at a high speed (500-1000 rev/min) while the substrate isheld by the substrate holding member 72, thereby removing superfluousplating liquid from the substrate and plating liquid remaining on thesubstrate-contacting portion 360, or portions in its vicinity, of thesealing member 244. After dewatering is completed and the substrate isremoved from the housing 70, the cylinder 314 for horizontal movement isactuated to move the nozzle head 302 toward the housing 70 and introduceit into the housing 70 through the opening 96 of the housing 70.Thereafter, the cylinder 318 for vertical movement is actuated to lowerthe nozzle head 302 so that the nozzle head approaches and faces thesubstrate-contacting portion 360 of the sealing member 244.

In this state, while rotating the housing 70 slowly in both directions(1-10 rev/min), sucking of the plating liquid by the actuation of thevacuum source 310 is conducted and, at the same time, a jet of acleaning liquid such as pure water is ejected from the cleaning liquidinjection nozzles 302 d toward the substrate-contacting portion 360, orportions in its vicinity, of the sealing member 244, thereby cleaningthe substrate-contacting portion 360, or the portions in its vicinity,of the sealing member 244. Thus, plating liquid remaining on thesubstrate-contacting portion 360, or the portions in its vicinity, ofthe sealing member 244 is sucked, together with cleaning liquid used forcleaning of the sealing member 244, by the plating liquid suctionnozzles 302 c. This can prevent plating liquid from remaining inside theplating liquid suction nozzles 302 c and clogging the nozzles when theplating liquid is dried.

The above suction-removing treatment effects removal of plating liquidremaining on half of the substrate-contacting portion 360, or theportions in its vicinity, of the sealing member 244. After completion ofthis treatment, the nozzle head 302 is withdrawn from the housing 70 inthe opposite manner to that described above, and the housing 70 isrotated horizontally by 180°. Thereafter, the nozzle head 302 isinserted into the housing 70 through an opening 96′ facing the opening96, and is then moved near to and faces the substrate contacting portion360, or the portions in its vicinity, of the sealing member 244 in thesame manner as described above. The same suction-removing treatment isthen carried out to effect removal of plating liquid remaining on theother half of the substrate-contacting portion 360, or portions in itsvicinity, of the sealing member 244.

The above plating liquid-removing treatment can suck and remove platingliquid remaining on the substrate-contacting portion 360, or theportions in its vicinity, of the sealing member 244 efficiently in ashort time, thus preventing an unremoved plating liquid becoming asource of particle generation. Further, clogging of the plating liquidsuction nozzles 302 c caused by residue of sucked plating liquid can beprevented.

It is also possible to easily remove plating liquid remaining on thesubstrate-contacting portion 360, or the portions in its vicinity, ofthe sealing member 244 merely by a sucking treatment using the platingliquid suction nozzles 302 c, without employing a cleaning treatmentusing the cleaning liquid injection nozzles 302 d, when the suckingtreatment is conducted at short intervals, such as a case where asucking treatment is conducted for every plating treatment.

As described hereinabove, according to the present invention, platingliquid remaining on a substrate-contacting portion, or portions in itsvicinity, at an inner circumferential edge of a substrate holding membercan be fully sucked and removed, forcibly. This can avoid a problem ofparticle generation which would be caused by unremoved plating liquidafter it has dried. Further, the plating apparatus of the presentinvention, which allows the substrate holding member to rotate, ensuresa good embedding of plated film in forming copper interconnects, e.g. bythe damascene method, and performs an improved plating, and in addition,can easily and promptly remove plating liquid remaining on thesubstrate-contacting portion, or the portions in its vicinity, of thesubstrate holding member. The plating apparatus eliminates the need torotate a plating liquid-removing device, thus enabling a simplifiedapparatus structure that requires a smaller space for installation.

Although certain preferred embodiments of the present invention havebeen shown and described in detail, it should be understood that variouschanges and modifications may be made therein without departing from thescope of the appended claims.

What is claimed is:
 1. A plating apparatus, comprising: a rotatablehousing provided with a substrate holding member for holding asubstrate; a plating process container for holding a plating liquidtherein; and a plating liquid removing mechanism for removing platingliquid remaining on a substrate-contacting portion of said substrateholding member at an inner circumferential edge of said substrateholding member, or for removing plating liquid remaining on portions ofsaid substrate holding member that are in the vicinity of saidsubstrate-contacting portion.
 2. The plating apparatus according toclaim 1, wherein said plating liquid removing mechanism has a platingliquid suction nozzle which can move close to said substrate-contactingportion and suck the plating liquid remaining on saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion. 3.The plating apparatus according to claim 2, wherein said plating liquidremoving mechanism also has a cleaning liquid injection nozzle which canmove close to said substrate-contacting portion and eject a cleaningliquid toward said substrate-contacting portion or said portions of saidsubstrate holding member that are in the vicinity of saidsubstrate-contacting portion.
 4. A plating apparatus, comprising: arotatable housing provided with a substrate holding member for holding asubstrate; and a plating process container for holding a plating liquidtherein; wherein said substrate holding member includes a sealing memberfor sealing an outer peripheral edge of the substrate, said sealingmember comprising a highly water-repellent high-tearing strength siliconrubber having a tensile strength of from about 10 Mpa to about 12 Mpa.5. A plating apparatus, comprising: a rotatable housing provided with asubstrate holding member for holding a substrate; a plating processcontainer for holding a plating liquid therein; and a plating liquidremoving mechanism for removing plating liquid remaining on asubstrate-contacting portion of said substrate holding member at aninner circumferential edge of said substrate holding member, or forremoving plating liquid remaining on portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion;wherein said substrate holding member includes a sealing member forsealing an outer peripheral edge of the substrate, said sealing membercomprising a highly water-repellent material.
 6. The plating apparatusaccording to claim 5, wherein said plating liquid removing mechanism hasa plating liquid suction nozzle which can move close to saidsubstrate-contacting portion and suck the plating liquid remaining onsaid substrate-contacting portion or said portions of said substrateholding member that are in the vicinity of said substrate-contactingportion.
 7. The plating apparatus according to claim 6, wherein saidplating liquid removing mechanism also has a cleaning liquid injectionnozzle which can move close to said substrate-contacting portion andeject a cleaning liquid toward said substrate-contacting portion or saidportions of said substrate holding member that are in the vicinity ofsaid substrate-contacting portion.
 8. A plating apparatus, comprising: arotatable housing provided with a substrate holding member for holding asubstrate; and a plating process container for holding a plating liquidtherein; wherein said substrate holding member includes a sealing memberfor sealing an outer peripheral edge of the substrate, said sealingmember having a substrate-contacting portion which has a flat topsurface and a cross-sectional shape of a spire.
 9. A plating apparatus,comprising: a rotatable housing provided with a substrate holding memberfor holding a substrate; a plating process container for holding aplating liquid therein; and a plating liquid removing mechanism forremoving plating liquid remaining on a substrate-contacting portion ofsaid substrate holding member at an inner circumferential edge of saidsubstrate holding member, or for removing plating liquid remaining onportions of said substrate holding member that are in the vicinity ofsaid substrate-contacting portion; wherein said substrate holding memberincludes a sealing member for sealing an outer peripheral edge of thesubstrate, said sealing member having a substrate-contacting portionwhich has a flat top surface and a cross-sectional shape of a spire. 10.The plating apparatus according to claim 9, wherein said plating liquidremoving mechanism has a plating liquid suction nozzle which can moveclose to said substrate-contacting portion and suck the plating liquidremaining on said substrate-contacting portion or said portions of saidsubstrate holding member that are in the vicinity of saidsubstrate-contacting portion.
 11. The plating apparatus according toclaim 10, wherein said plating liquid removing mechanism also has acleaning liquid injection nozzle which can move close to saidsubstrate-contacting portion and eject a cleaning liquid toward saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion.12. A plating apparatus comprising: a rotatable housing provided with asubstrate holding member for holding a substrate; a plating processcontainer for holding a plating liquid therein; and a plating liquidremoving mechanism for removing plating liquid remaining on asubstrate-contacting portion of said substrate holding member at aninner circumferential edge of said substrate holding member, or forremoving plating liquid remaining on portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion;wherein said plating liquid removing mechanism has a plating liquidsucking member which is allowed to be introduced into said housingthrough an opening of said housing and to move near to said substrateholding member, and wherein said plating liquid removing mechanism isfor removing the plating liquid remaining on said substrate-contactingportion, or said portions of said substrate holding member that are inthe vicinity of said substrate-contacting portion, while said platingliquid sucking member faces said substrate-contacting portion and saidsubstrate holding member is rotated.
 13. The plating apparatus accordingto claim 12, wherein said plating liquid sucking member includes aplating liquid suction nozzle which can move close to saidsubstrate-contacting portion and suck the plating liquid remaining onsaid substrate-contacting portion or said portions of said substrateholding member that are in the vicinity of said substrate-contactingportion.
 14. The plating apparatus according to claim 13, wherein saidplating liquid sucking member also includes a cleaning liquid injectionnozzle which can move close to said substrate-contacting portion andeject a cleaning liquid toward said substrate-contacting portion or saidportions of said substrate holding member that are in the vicinity ofsaid substrate-contacting portion.
 15. A plating method, comprising:plating a substrate held by a substrate holding member of a rotatablehousing; rotating said housing to remove plating liquid remaining onsaid substrate and said substrate holding member; removing saidsubstrate from said housing through an opening of said housing; causinga plating liquid sucking member of a plating liquid removing mechanismto face said substrate holding member by introducing said plating liquidremoving mechanism into said housing through said opening; and removingplating liquid remaining on a substrate-contacting portion of saidsubstrate holding member at an inner circumferential edge of saidsubstrate holding member, or removing plating liquid remaining onportions of said substrate holding member that are in the vicinity ofsaid substrate-contacting portion, while said plating liquid suckingmember closely faces said substrate holding member and said substrateholding member is rotated.
 16. The plating method according to claim 15,wherein said plating liquid sucking member includes a plating liquidsuction nozzle, and removing the plating liquid remaining on saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portioncomprises moving said plating liquid suction nozzle close to saidsubstrate-contacting portion and using said plating liquid suctionnozzle to remove the plating liquid remaining on saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion.17. The plating method according to claim 16, wherein said platingliquid sucking member further includes a cleaning liquid injectionnozzle which can move close to said substrate-contacting portion andeject a cleaning liquid toward said substrate-contacting portion or saidportions of said substrate holding member that are in the vicinity ofsaid substrate-contacting portion.
 18. The plating apparatus accordingto claim 1, wherein said plating liquid removing mechanism is forremoving the plating liquid remaining on said substrate-contactingportion, or said portions of said substrate holding member that are inthe vicinity of said substrate-contacting portion, while said platingliquid removing mechanism closely faces said substrate-contactingportion and said substrate holding member is rotated.
 19. The platingapparatus according to claim 18, wherein said plating liquid removingmechanism includes a plating liquid suction nozzle which can move closeto said substrate-contacting portion and suck the plating liquidremaining on said substrate-contacting portion or said portions of saidsubstrate holding member that are in the vicinity of saidsubstrate-contacting portion.
 20. The plating apparatus according toclaim 19, wherein said plating liquid removing mechanism also includes acleaning liquid injection nozzle which can move close to saidsubstrate-contacting portion and eject a cleaning liquid toward saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion.21. The plating apparatus according to claim 5, wherein said platingliquid removing mechanism is for removing the plating liquid remainingon said substrate-contacting portion, or said portions of said substrateholding member that are in the vicinity of said substrate-contactingportion, while said plating liquid removing mechanism closely faces saidsubstrate-contacting portion and said substrate holding member isrotated.
 22. The plating apparatus according to claim 21, wherein saidhighly water-repellent material comprises a highly water-repellenthigh-tearing strength silicon rubber having enhanced tensile strength.23. The plating apparatus according to claim 22, wherein said platingliquid removing mechanism includes a plating liquid suction nozzle whichcan move close to said substrate-contacting portion and suck the platingliquid remaining on said substrate-contacting portion or said portionsof said substrate holding member that are in the vicinity of saidsubstrate-contacting portion.
 24. The plating apparatus according toclaim 23, wherein said plating liquid removing mechanism also includes acleaning liquid injection nozzle which can move close to saidsubstrate-contacting portion and eject a cleaning liquid toward saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion.25. The plating apparatus according to claim 22, wherein said siliconrubber has a tensile strength of from about 10 Mpa to about 12 Mpa. 26.The plating apparatus according to claim 8, wherein the spiredcross-sectional shape of said sealing member is such that plating liquidcan remain on a surface of said sealing member that is positionedinwardly of said flat top surface.
 27. The plating apparatus accordingto claim 8, wherein the spired cross-sectional shape of said sealingmember is defined by said flat top surface, an inner planar surface ofsaid sealing member that slopes away from said flat top surface, and anouter planar surface of said sealing member that slopes away from saidflat top surface.
 28. The plating apparatus according to claim 9,wherein said plating liquid removing mechanism is for removing theplating liquid remaining on said substrate-contacting portion, or saidportions of said substrate holding member that are in the vicinity ofsaid substrate-contacting portion, while said plating liquid removingmechanism closely faces said substrate-contacting portion and saidsubstrate holding member is rotated.
 29. The plating apparatus accordingto claim 28, wherein the spired cross-sectional shape of said sealingmember is such that plating liquid can remain on a surface of saidsealing member that is positioned inwardly of said flat top surface. 30.The plating apparatus according to claim 29, wherein said plating liquidremoving mechanism includes a plating liquid suction nozzle which canmove close to said substrate-contacting portion and suck the platingliquid remaining on said substrate-contacting portion or said portionsof said substrate holding member that are in the vicinity of saidsubstrate-contacting portion.
 31. The plating apparatus according toclaim 30, wherein said plating liquid removing mechanism also includes acleaning liquid injection nozzle which can move close to saidsubstrate-contacting portion and eject a cleaning liquid toward saidsubstrate-contacting portion or said portions of said substrate holdingmember that are in the vicinity of said substrate-contacting portion.32. The plating apparatus according to claim 9, wherein the spiredcross-sectional shape of said sealing member is defined by said flat topsurface, an inner planar surface of said sealing member that slopes awayfrom said flat top surface, and an outer planar surface of said sealingmember that slopes away from said flat top surface.